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Comments 12051 to 12100:

  1. A Green New Deal must not sabotage climate goals

    The Green New Deal looks very well intended and a good overall philosophy, but it looks like it requires hundreds of complicated regulations which makes it unweildy. All because it lacks a price on carbon! and a simple idea like a carbon tax and cap and trade.

    It also proposes the government build and fund billions in infrastructure, which is economically a high risk approach given federal debt is already high. A carbon tax and / or just a few limited subsidies would achieve the same end goal by pushing the private sector to build renewable energy.
    The ideas seem to come form the New Deal of the 1930's but times were different then.

    I think the idea might be popular with the public because it doesn't involve a tax and leaves everything to the government, but I can't see politicians loving it, and they decide on legislation.

    Just my gut reaction. I could be wrong. Its hard to predict what ideas will gain traction.

  2. 1934 - hottest year on record

    LTO - I agree it would be better if we had side-by-side chart of error-bars, but again, the chart is valid for the purpose. Even with double the estimated error, the essential picture of differences between 1934 and now is unchanged - it is fit for purpose.

    As it is, as far as aware from the papers, a "map" of error estimates does not exist. The validation and error estimation methods instead work by latitude-range and sometimes ocean (eg the error bars for north atlantic are less than for north pacific).

  3. SkS Analogy 18 - Cliff jumping and temperature changes

    nigelj

    Ruddiman has a very plausable theory on why this interglacial has been so much more stable, climate wise, than previous interglacials.  See Plows Plagues and Petroleum.  A fascinating read.

  4. SkS Analogy 18 - Cliff jumping and temperature changes

    The last thing you need when standing on the edge of a cliff is a great leap forward.

  5. 1934 - hottest year on record

    And here's a discussion of that thesis at 'And Then There's Physics', which points out that the thesis was completed under the direction of two well known climate deniers.

    The science in that thesis is lousy, and it's not. a. good. source.

  6. 1934 - hottest year on record

    LTO - I looked back through your previous comments in your thread, and found your posting of a thesis by a John McLean, which somehow argues that HadCRUT is wholly unreliable. Is this the same John McLean who in 2011 stated (oh, so incorrectly) that temps were about to return to 1956 levels?

    If so, I would humbly point out that he's not a good reference due to past demonstrated errors. His temperature predictions are among the worst I'm aware of.

  7. The Methane 'Time Bomb': How big a concern?

    "What we do see in the geological record is the isotopic fingerprint of massive methane clathrate releases during periods of rapid warming from a prior stable state.

    Which is exactly what is happening now."

    Respectfully, those periods were directly related to, and a result of, Large Igneous Province events.  This has been covered by this venue before.  But to the best of my knowledge, the evidence supporting a firing of the Clathrate Gun since the PETM is scarce (and the evidence of a firing then is mixed).

    What the paleo record and recent research shows is that clathrates have endured periods of warmer temperatures than even now for even millions of years and remained in stable configurations.  Obviously, that is not proof that clathrates will remain immune to future warming, but since in science we use the past as a guide to the future, it does lend some measure of confidence that time remains to make a difference for those coming after us.

  8. citizenschallenge at 01:28 AM on 1 February 2019
    New research, January 14-20, 2019

    Ari, thanks for continuing with this thankless task.  It is important!

    But I'm here to ask a question: would you know the first time the PDO was incorporated into climate models?

    I'm asking because I've read recent claims that climate models do not incorporate the PDO.  I can imagine that perhaps long-term models may not incorporate the PDO because it's actually irrelevant to what they are looking at (since the PDO only pushes heat around).  But, that's personal guessing.  

    Just seems to me the PDO has been studied a great deal and that the accumulating information would have been plugged into climate models - and if not, there's probably a good explanation that I would love to learn about.

    But I don't know, I'm no scientist, though I do try to keep up with their findings.

    Ari, can you (or anyone else) add any clarifying details?

  9. 1934 - hottest year on record

    LTO - If you are so concerned regarding the infill for certain regions in 1934 (an argument I find quite thin; the correlation strengths for those infills are well tested and established), then by all means simply compare the sampled areas in 1934 directly with the identical areas in 2016 - ignore the regions of increased coverage. And you will find, as per the OP, that 1934 was warm in a few regions such as the US, but overall the globe wasn't particularly warm (perhaps 0.1C below the 20th century average), and that the last few years are running perhaps 1C above the 20th century average, both in the subset well sampled in 1934 and in the world as a whole.

    In short, the climate myth claiming that 1934 was a hot year, and thus attempting to refute general temperature assessments, is both wrong and a bad idea, scientifically speaking.

    Given that, just what is your complaint about the OP?

  10. SkS Analogy 18 - Cliff jumping and temperature changes

    I grew up in Minnesota, and winter was not winter until we had one or two weeks when daily highs were below 0 and lows were in the -20's or colder. Now we have a couple days when it's cold, and this weekend we will be in the higher 30's low 40's!

  11. 1934 - hottest year on record

    LTO @96.

    Firstly, my apologies for the "... and this refers to both land and ocean data" within my comment @94. This was part of a rather-too-long passage that was cut, and should have been cut in its entirety. (This cut passage concerned the "reliability" comment on the ERSST info web-page being part of the caption for a missing graphic.)

    Secondly, looking at your many comments down this thread, you "beef" is that you consider it inappropriate to in-fill temperatures on an anomaly map. You term this in-fill for the 1934 map in the OP (actually a 5-year period centred on 1934) "exceptionally misleading," "massively misleading and something of a work of fiction," "fanciful" and suggest it is unjustifiable. You appear to expect coverage to be at least ten stations per ~200km square. And despite the long-long interchange since #59 up-thread, I don't see any movement from that position.

    You appear to want folk here to furnish you with station-number/measurement-numbers for some remote part of the world at some time in the past; this information to demonstrate that you are justified in branding the anomay map in the OP "exceptionally misleading." But such a conclusion ignores the ability of folk to produce such anomaly maps that remain remarkably accurate with far fewer data. I think you are less after understanding (which you have said is your purpose) and more are looking for a research assistant to furnish you with ammunition for your erroneous "beef."

    Thirdly, I am aware that you asked a question @87. Demanding an answer isn't a good way of getting an answer. Besides, I am not entirely sure an answer would be helpful to your understanding.

    So perhaps there is need to restructure your 'enquiry' here. So far, it is producing a lot of words and with very little coherence.

  12. The Methane 'Time Bomb': How big a concern?

    It may require some fundamental shift to destabilize some of these methane hydrate deposits, the concern I have is we are shifting the entire global system of heat transfer and storage from a relatively stable state to one that is in flux to a much different system. One not ever seen before when we consider continental arrangement, Solar output and ocean circulation.

    There was a paper by Hansen and his GISS team a number of years ago about research that showed it was possible that as the poles continue to warm and deep water submergence off of Greenland slowed it a new area of deep water submergence could form in temperate zones introducing relatively warm water to the deep ocean.

    There are so many variables at work here that I don't think a massive methane release is off the table. It may not happen for decades or centuries, but we could be creating the conditions right now that triggers such a release at a later time and not even know it.

    What we do see in the geological record is the isotopic fingerprint of massive methane clathrate releases during periods of rapid warming from a prior stable state. 

    Which is exactly what is happening now.

  13. 1934 - hottest year on record

    Remarkable that someone considered something in my post at #96 to be inflammatory and yet lets eclectic spew insult after insult cf #97.

    Scadden: you're persisting in refusing to engage on the points I'm actually making about the 1934 chart. You say that uncertainty and large error bars aren't thr same as don't know, but this depends on what the question is, and what you're trying to do with the data. The 1934 chart doesn't present any error bars, uncertainties or indications of statistical significance at all nor acknowledge the massive spread in uncertainties across different parts of the globe. The error is not homogeneous. This, as I've been repeatedly saying, is incredibly misleading as it leads people to think we know far more than we actually do.

    Moderator Response:

    [JH] Moderation complaint snipped.

    Please note that posting comments here at SkS is a privilege, not a right.  This privilege can and will be rescinded if the posting individual continues to treat adherence to the Comments Policy as optional, rather than the mandatory condition of participating in this online forum.

    Moderating this site is a tiresome chore, particularly when commentators repeatedly submit offensive or off-topic posts. We really appreciate people's cooperation in abiding by the Comments Policy, which is largely responsible for the quality of this site. 
     
    Finally, please understand that moderation policies are not open for discussion.  If you find yourself incapable of abiding by these common set of rules that everyone else observes, then a change of venues is in the offing.

    Please take the time to review the policy and ensure future comments are in full compliance with it.  Thanks for your understanding and compliance in this matter.

     

     

  14. The Methane 'Time Bomb': How big a concern?

    I used to interact briefly with methane hydrate researchers at the USGS, mostly from a resource assessment perspective. From what I remember, being a non-clathrate specialist, was that they (USGS, i.e. Carolyn Ruppel and Tim Collett) didn't think massive marine destabilization via global warming was likely. I remember someone saying that ocean waters are relatively unsaturated with methane and that the methane wouldn't be able to rise to the surface.. I could be totally wrong on this!

    I do know that the going theory is that massive onshore methane hydrates deposits are "frozen" thermogenic natural gas fields that had probably been there for a long time, well before the icehouse climate we are or used to be in. Therefore, it's unlikely that these frozen gas fields will destabalize and make it to the atmosphere--they are already trapped so to speak.

    The methane hydrate stability zone, onshore Artic Alaska, is typically around 800' to over 4,000' below the surface, and would take a very long time to thaw out anyways. By then the earth will probably be 8 degrees C warmer--game over!

  15. SkS Analogy 18 - Cliff jumping and temperature changes

    Regarding America's current very cold weather: NOAA's Brilliant Response To Trumps Climate Tweet

  16. SkS Analogy 18 - Cliff jumping and temperature changes

    michael sweet @3 

    You're right to advise caution as weather extremes are often misrepresented as "proof" that a long term warming is not taking place.

    It's important to note that global warming and climate change is a long term trend taking place over the entire globe. And while local cold weather records may be broken, this is almost certainly a result of the chaotic disruption of weather caused by a global transition to a warmer Earth.

    In the case of some periods of cold weather in North America, this may be due to the fact that generaly warmer temperatures in the Arctic have disrupted atmospheric circulation that in the past has tended to isolate very cold air masses above the Arctic in the winter.

    This can result in unusual weather across North America such as a few year ago when we in Edmonton Alberta were experiencing unusually mild weather well above freezing when Florida was seeing sub zero weather and snow.

  17. SkS Analogy 18 - Cliff jumping and temperature changes

    I am sorry, in the USA there were 7 cold records in the past 365 days.

  18. SkS Analogy 18 - Cliff jumping and temperature changes

    Nigelj,

    Read the link to Cliff Mass.  The data show that cold waves are much less frequent and are warmer than they used to be.  They are warming faster than the global average.

    If you look at the all time temperature records at the NCDC (linked above) in the past 365 days in the USA there were 181 hot records and only 5 cold records (!!!).  That is because hot records are much more common than they used to be and cold records are much less common.

    In the NCDC all time global records in the past 365 days there were 568 hot records and only 18 cold records.  I do not know how many global sites they use.  Many news reports call temperatures that are the coldest for the past 50 years a "record cold" even though it used to be much colder.  I also heard "coldest in a generation" which is generally only 30 years.  People forget what it used to be like.

  19. SkS Analogy 18 - Cliff jumping and temperature changes

    The cold weather in America might well be nothing truly record setting, but there is some preliminary evidence climate change is altering the behaviour of the polar vortex, and leading to potentially lengthy and more frequent periods of very cold winter temperatures in America.

    en.wikipedia.org/wiki/Polar_vortex#Climate_change

  20. SkS Analogy 18 - Cliff jumping and temperature changes

    Doug C.:

    While many mass media outlets have reported record cold, it has not yet been as cold as it used to be from 1900-1950.

    At the NCDC temperature records page they currently record no monthly cold lows or monthly cold highs set in the past 7 days.  I have seen several reports of daily records (not monthly or yearly records) that might be set tonight.  It is possible that the data has not had time to be recorded yet, we should check back in a few days.  Since it is January a yearly cold record would be unusual cold while a daily record is not as significant.

    Cliff Mass has a post that shows cold spells are warming faster than average global warming (hat tip to snape at Tamino's).

    Until the data shows a few all time lows the "record polar vortex" is so much smoke.  A post at Tamino's showed that in Minneapolis the number of days per year -20F or lower has dramatically decreased for the past several decades.  I heard a newsman report on PBS that it was the "coldest it had been in 50 years".  Global warming really got going 50 years ago.  A 50 year record would be a cold, but not exceptional day, in the 1920's.

    During the "Summer in Wnter" in 2012, in at least 4 locations the low temperature at night was higher than the previous highest temperature ever recorded (at locations with long periods of record).  Several daily records were broken by 30F.  We will see if this cold spell actually sets any significant records next week.   

    The deniers like to hype average cold spells as record setting, don't believe them.  If it is the coldest day in 20 years it is as cold as an average cold day 75 years ago.

  21. The Methane 'Time Bomb': How big a concern?

    “Never argue with a fool, onlookers may not be able to tell the difference.” - Mark Twain

    There are no greater fools in todays world than those who are intentionally denying fossil fuels driven climate change.

    They have won the decades long struggle to face this crisis by pulling the rest of society most notably the entire field of science into the mud where everyone is seen in the same irresponsible and foolish light.

    Those of us who really are interested in being the best not worst we can be need to step totally out of this paradigm and make the necessary changes.

    In the long term we will all be so much the better for it.

  22. The Methane 'Time Bomb': How big a concern?

    Doug_C@8 Well said. So let's stop asking people if they believe in GW/CC and just take polls about what we should do about it. By asking if people believe GW/CC is occurring and if ask about causation, we are leading into the industry that is standing in the way of progress. That is, we legitimize the false debate by asking about the false ndebate.

  23. SkS Analogy 18 - Cliff jumping and temperature changes

    According to the work of James Hansen et al climate sensitivity roughly follows a U-shaped curve, which means the further you get from your approximately stable start point the faster change occurs.

    Hansen and Sato Estimate Climate Sensitivity from Earth's History

     

    The longer we push this process the more dangerous it gets with major tipping points like the loss of polar ice sheet stability, ice albedo effect and altering of ocean and atmospheric circulation.

    We're now experiencing in North America what a destabilized Arctic vortex means with very cold air that usually sits over the North Pole during winter being pulled deep into the continent producing record cold in many places.

    We'll also see these extremes in coming years as ocean levels increase and record storm activity creates record storm surges. Not a possibility now, a statistical certainty given the conditions.

    A safe level of CO2 is almost certainly below;

    350 ppm

  24. 1934 - hottest year on record

    Validation and errors have been re-examined a number of times, as the explicitly stated in the Huang 2016 method paper and easily followed in the bibliography. As a side note BEST was set up because of perceived errors in the temperature record. They tried a new methodology (always good) but ended up discovering that that existing methodology worked after all. Perception is not reality, but BEST credit, this is science and skepticism working as it should.

    What is peeving for me and other commentators is that your insistence "we know things about the global distribution of temp anomalies that we simply don’t" Uncertainty and large error bars are not the same as "dont know". Huang comments on pre-1940 data are more deeply discussed in the methods and earlier papers. 1940 is when change in measurement methodology occurred as well as issues with coverage. These all combine to uncertainties of up to 0.9C in lower southern hemisphere oceans. Double that if you like and the difference between 1934 and now is still pretty much as depicted by the figure.

    Sparcity of measurement does not translate into unknowable. You can use modern satellite data to show anomalies are spatially correlated over large distance and estimate errors in unsampled areas. You dont appear to have read how the anomaly baselines are actually calculated. Try Smith and Reynolds 2003 and note especially the discussion about high and low frequency distributions. And, yes, weather models are useful. Humidity measurements made down wind constrain what temperatures upwind can be etc etc. And, no you dont have to take it on faith. Reanalysis models do extensive validation otherwise noone would trust them.

  25. The Methane 'Time Bomb': How big a concern?

    Evan @7

    Unfortunatley we are now in a position of triage having to decide what we can save and what resources we have to do so.

    The loss of coral reef systems alone is going to have a profound effect on how life in the oceans behave. One quarter of marine species are dependent on coral reefs for some or all of their lifecycle. The oceans are the main lungs of the planet and home to most life here.

    The loss of glaciers is going to also have major impacts on us and the ecosystems around us in many places. I'm from British Columbia and have been familiar with glaciers all my life and the rivers and lakes they feed. It's really sobering to think of a BC... and many other places... with little or no glaciers.

    As a kid in the early 1970s I remember a family trip through Glacier national park on the Canada-US border and the many glaciers that gave the park its name. Most are now gone in a pattern repeated globally.

    Extreme Ice Survey

    The polar ice sheets have already lost their stability and are losing ice at an incredible rate, far faster than models that treat them as solid blocks melting from the outside predicted.

    And it goes on an on, we have upset a fundamental balance that determines one of the most important factors on Earth, how warm it is on the planet's surface. And it is still treated as a relatively minor issue by far too many people, many of them in positions that need to take responsible action, not keep promoting the same activities that have brought us here.

    I also have family who work in the oil industry in Alberta and I get how important it is to people there. But it is incredibly frustrating to try to explain to people how what they are doing right now to meet their immediate needs is going to make it very difficult to impossible for them and their kids to meet those needs in just a few decades. With major emergencies along the way like the record flooding in southern Alberta in 2013 and the massive wildfires that burned down Fort McMurray in 2016.

    There are real actions and solutions to this growing catastrophe but they require a willingness to change. Sadly something that is still lakcing in many people, who are somehow able to ignore the fact that the Earth is already changing now for the worst.

    Real change to a low carbon sustainable energy and economic model has so many benefits that it no longer makes any sense at all to talk about fossil fuels as anything else but a disaster on a scale that makes CFCs, DDT and many other human created ecological and social problems minor in comparison.

  26. SkS Analogy 18 - Cliff jumping and temperature changes

    The current interglacial period called the Holocene has had very stable temperatures (within 1 degree of variation) over about the last 10,000 years, and this perfectly suits agriculture, which appeared early during this period and flourished. Prior to that period during the ice age climate variation had huge global swings.

    Agriculture loves a stable climate, and has been the foundation of advanced human civilisation. We are putting all this at risk. This guy is a chemistry teacher and has some really good thoughts on it.

  27. The Methane 'Time Bomb': How big a concern?

    Doug_C@6 Well said.

    We need to stop the polls that ask if so and so believes in GW/CC and whether they think humans are contributing.

    Just ask, "What do you think the consequences of GW/CC will be?"

    "What are you prepared to do to decrease GHG emissions?

    We don't ask people if they think the Earth is round or if the sun orbits the Earth. Time to stop asking people what they think about science they don't know any better than orbital dynamics.

    We need to lead people towards action and solutions.

  28. The Methane 'Time Bomb': How big a concern?

    nigelj @3

    We already have crossed climatic tipping points that already have profound impacts on all our lives and the biosphere as a whole.

    It's not pessimism to keep pointing out that coral reef systems are probably going largely extinct in what is an instant in geological terms.

    That the cryosphere is in rapid retreat that is going to have significant impacts globally for people and ecosystems.

    That extreme weather events are creating hellish conditions already and more. 

    And we're still at the same rate or higher of carbon dioxide emissions as decades ago when some of the earliest experts were warning of this growing catastrophe.

    And it is a catastrophe already with the very real potential to eclipse all other catastrophes in human history. In fact it is guaranteed to do so if we just keep collectively doing what we're doing for a little bit longer.

    The inertia in change created by this one radiative forcing is incredible and we keep adding to it each year based on the myth that we can suddenly turn it around when it becomes so destructive that it is impossible for anyone to deny the danger.

    It's iike if a mob of people were levering a massive boulder on a slope above a town. It moves slowly at first and they keep up the process of forcing to a gradually higher and higher speed as the slope it is on increases. This is exactly what is happening with fossil fuels created climate change. 

    The longer it goes on and the more it is forced the more force it has until it is totally out of control and every in its path is destroyed.

    And a huge part of the debate is still if it's even happening.

  29. Water vapor is the most powerful greenhouse gas

    I can't add scientific value to this debate though I am a voracious reader on the subject. Just want to say how refreshing it is to see Chris & Mizimi having a scientific debate without the usual vitriolic climate denier criticism.

    Have to say I feel Mizimi has a slight edge & remain convinced that the sun is the primary driver of climate change.

    Moderator Response:

    [DB] The incoming energy from the sun has been well-documented and studied, for literally generations of scientists.  That the sun plays almost no role in the warming of the surface of the Earth over the past 50+ years is also well-researched, well-documented and uncontentious in any scientific sense.

    Per NASA, it's not the sun

    LINK1

    LINK2

    From the 4th National Climate Assessment, Volume 2, released by the Trump Administration:

    "Scientists have understood the fundamental physics of climate change for almost 200 years. In the 1850s, researchers demonstrated that carbon dioxide and other naturally occurring greenhouse gases in the atmosphere prevent some of the heat radiating from Earth’s surface from escaping to space: this is known as the greenhouse effect.

    This natural greenhouse effect warms the planet’s surface about 60°F above what it would be otherwise, creating a habitat suitable for life. Since the late 19th century, however, humans have released an increasing amount of greenhouse gases into the atmosphere through burning fossil fuels and, to a lesser extent, deforestation and land-use change. As a result, the atmospheric concentration of carbon dioxide, the largest contributor to human-caused warming, has increased by about 40% over the industrial era.

    This change has intensified the natural greenhouse effect, driving an increase in global surface temperatures and other widespread changes in Earth’s climate that are unprecedented in the history of modern civilization.

    Global climate is also influenced by natural factors that determine how much of the sun’s energy enters and leaves Earth’s atmosphere and by natural climate cycles that affect temperatures and weather patterns in the short term, especially regionally.

    However, the unambiguous long-term warming trend in global average temperature over the last century cannot be explained by natural factors alone.

    Greenhouse gas emissions from human activities are the only factors that can account for the observed warming over the last century; there are no credible alternative human or natural explanations supported by the observational evidence.

    Without human activities, the influence of natural factors alone [which includes the sun] would actually have had a slight cooling effect on global climate over the last 50 years."

    LINK3

  30. 1934 - hottest year on record

    LTO @96 , 

    further to my points @95 , have you come to any substantive useful conclusions about AGW and mainstream climate science?

    Thus far, your posts have been remarkably discursive and deficient in critical thinking.

  31. 1934 - hottest year on record

    Hi MA

    You may notice that ‘beef’ was first used in #91, and not by me. 

    I’ve set out my concerns now a number of times. I asked you some questions in #87 you haven’t answered. If you don’t know the answers, it‘s fine to admit it. My purpose here isn’t to trick anyone, just to increase my understanding of the relative uncertainties. There are indeed many profound omissions in my knowledge on this topic, which is precisely why I’m here. I’ve never pretended otherwise. I’d add with certainty that there are many profound omissions in the knowledge of people who have made up their minds that climate change will destroy the world in 12 years, as well. 

    There’s an irony here that a site called sceptical science treats questions about extremely complicated data manipulation with dismissive rudeness. You haven’t done this - your answers have been exceptionally informative - but the same can’t be said of some of your colleagues. It isn’t my job to ‘distinguish’ myself from different people asking different questions, although frankly I’d have thought that the ‘asking different questions’ element would do this.

    Your claim that the comment about ERSST data before 1950 being unreliable (which I quoted in full in #80) is referring to both land and sea data isn’t apparent at all, and the page appears to be talking solely about The Extended Reconstructed Sea Surface Temperature (ERSST) dataset.  https://www.ncdc.noaa.gov/data-access/marineocean-data/extended-reconstructed-sea-surface-temperature-ersst-v5 It may be another profound omission of mine to think that this data set is just, you know, sea surface temperatures, but I suspect I’m on more solid footing here. I’m not sure what the relevance of the point is, either way, as it doesn’t move anything forward from my comments at #92

    As to the point about statistical error analysis, I suspect you’re being disingenuous. If not, read this and prepare to be amazed: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1182327/

    Moderator Response:

    [DB] Inflammatory and off-topic snipped.

  32. 1934 - hottest year on record

    LTO , my comment is a general one :-

    Granted that our knowledge of localized climatic conditions becomes increasingly imperfect as we look backward through the past century (and indeed, past millennium) . . . is there any substantive conclusion (from that truism) which you wish to present to the readers of this thread?

    You make the valid point that there should be better understanding of "statistics and treatment of errors".   But (so far) you have not drawn any substantive conclusion (from that point) regarding the science of modern climate.   Are you trying to show that the mainstream/consensus assessment of AGW is wrong in a major way?   And if so . . . how is it wrong?

    You yourself have indicated ( in #87 , though in a passive way ) that the contrarian scientists who undertook the BEST project did end up in confirming the mainstream science.   Which is also confirmed by the simple physical evidence of melting ice / rising sea level / oceanic acidification / species migration / etcetera.

    And as for "statistics and treament of errors" . . . none of us should forget that the methodology of statistics has the primary purpose of illuminating/assessing scientific "fact" (or more grandly, "truth").   I am sure you would like to agree that statistics ought not to be used to obfuscate, or to persuade the reader toward falsehoods & pseudo-science.   Of course.

  33. The Methane 'Time Bomb': How big a concern?

    To my mind there is huge danger. With melting snow and ice you are getting more water vapour in the air. Water vapour radiates infrared radiation and snow and ice are almost like black bodies when it comes to infrared radiation. Besides this, the dark rock left behind after melting will absorb far more radiation than snow. The extra infrared radiation from greenhouse gases is mainly in the 5 to 8 micron wavelength range and above about 14 microns in wavelenth. This downwelling sky radiation concentrates itself in the top few mm of the sea surface causing high sea surface temperatures which will lead to rapid evaporation.

  34. 1934 - hottest year on record

    LTO @92/93,

    Perhaps the difficulty you have with your "beef" is that it has a great similarity to that more commonly persented by folk who are in denial about AGW and who argue robustly against the very evidence itself. Given that similarity, you do need to be on the very top of your game to differentiate yourself from such contrarians. So not grasping that GISS LOTI is a combination of surface air temperature (GHCN) surface sea temperature (ERSST) is a rather profound omission. I would also add that the lack of patience with those comments challenging you is also something of a contrarian characteristic.

    Picking up on your assertion that the ERSSTv5 info web page says that "explicitly acknowledge(s) on their website unreliability of data from the 1940s and earlier"; this is incorrect. The statement made is "Note that the data are more reliable after the 1940s" and this refers to both land and ocean data. What is 'reliable' depends on your purpose. Note the description following that statement. So if that is to compare the ERSST 2° × 2° grided data cell-by-cell (2° of latitude is 210km), then 'reliability' pre-1950 may be more of an issue for you.

    If you have specific concerns with 'uncertainty' regarding these data, it would be good if you set them out. And by that, I mean describing them properly rather than presenting accusative statements such as "the vast majority of scientists ... don’t really understand statistics and treatment of errors. It’s not a trivial point..." or suggesting there is "imaginary 1934 data ... No such measurements exist in 1934" being presented as real. If your "beef" were to rattle out levels of accuracy in temperature records, we wouldn't expect such language.

  35. 1934 - hottest year on record

    Hi Michael

    I don’t think you’re a serious part of the discussion here. My post at #69 specifically discusses data from Hansen’s 1987 paper, and overlays those figures against the 1934 chart at the top of this article to illustrate my point, which you haven’t addressed. Your asserting that that isn’t there makes you look like a fool. I’m relatively sure that isn’t actually the case, although the uncertainty in that belief is increasing rapidly. Your only purpose here appears to be to insult me, as opposed to explaining concepts or arguing points of view. I’m learning a huge amount about this topic and the myriad complexities from the discussions I’m having on this site, but not from you. Please either change your tone or stop harassing me.

    Moderator Response:

    [JH] Antagonistic, ad-hominem snipped. In addition, you are now skating on the thin ice of excessive repetition which is also prohibited by the SkS Comments Policy

    Please note that posting comments here at SkS is a privilege, not a right.  This privilege can be rescinded if the posting individual treats adherence to the Comments Policy as optional, rather than the mandatory condition of participating in this online forum.

    Please take the time to review the policy and ensure future comments are in full compliance with it.  Thanks for your understanding and compliance in this matter.

  36. 1934 - hottest year on record

    Hi Scadden

    Accepted! :) My beef is that the 1934 chart gives the impression we know things about the global distribution of temp anomalies that we simply don’t. I consider it to be extremely misleading, even if the point of this article (1934 was only hot in localised areas) is true. Generally, I‘m finding there is a real lack of acknowledgement and proper treatment of uncertainties. Unfounded certainty raises red flags, and is unscientific. 

    If you’ve got a solid background in experimental science you’ll know that the vast majority of scientists (particularly those in softer fields) don’t really understand statistics and treatment of errors. It’s not a trivial point, nor is validation of data. As we get more And more measurement data, it becomes less and less reasonable to rely on old analyses of validation and associated errors. As I understand it Berkeley Earth was set up precisely because of myriad errors in climate data analysis (even if the eventual conclusions on land temperature changes were in line with prior analysis).

    To illustrate what I mean, see the annotated image here. https://imgur.com/a/TkeiRrt There are ‘features’ in areas where there was probably no data collected in 1934, meaning that what we’re looking at in the areas I’ve highlighted is a largely imaginary baseline (I.e. using infilled data modelling for much of the 20th century) overlaid with imaginary 1934 data. If you look at the areas I’ve highlighted in the 2016 data, you can see there are real features that you’d only identify from having actual measurements. No such measurements exist in 1934, and so the model just assumes everything is cold, and makes up some features to give the impression of being realistic. Do you see my point?

    Re the SST data, I address the Huang et al data set in #80 above - ERSST explicitly acknowledge on their website unreliability of data from the 1940s and earlier. I must say I’m a bit confused now about whether the chart is supposed to be sea surface temperatures or air temperatures. Obviously the two are linked, but they’re not the same thing.

  37. Trenberth on Tracking Earth’s energy: A key to climate variability and change

    Tobirh,

    If you look carefully at figure 1 the numbers are rounded.  Incoming 341.3 is rounded to 341.  Outgoing 101.9 is rounded to 102 and 238.5 is roumded to 239.  If you add up the unrounded numbers they leave 0.9 w/m2 absorbed.

  38. The Methane 'Time Bomb': How big a concern?

    The video was a snap shot of different points of view, with no unifying dialogue or conclusions. This could be seen as thought provoking and non preachy, but some people might conclude "nobody really knows what's going on". Is this the message we want to send?

  39. The Methane 'Time Bomb': How big a concern?

    I do not downplay the climate problem, the climate problem is huge, but there is a danger in too much unfounded pessimism that we have already crossed tipping points (change irreversible) would create a feeling that its pointless reducing emissions.  Wouldn't it? In fact the tipping point for arctic summer ice is from 1-3 degrees c, greenland ice sheet is 1-3 degrees, for artic winter ice is 5degrees c, permafrost it is 6 degrees c, so there is still a chance to avoid these. List of all tipping points here. A slim chance in some cases.

  40. Trenberth on Tracking Earth’s energy: A key to climate variability and change

    Tobirh @271 , 

    my impression is that the 0.9W/m2 is only an approximation.  You will note that the Fig. 1 description mentions that they are talking of the energy balance for the period 2000 - 2005 (so about 15 years before today).

    Today's imbalance is approximately twice that 0.9 amount.

    But the TOA [Top Of Atmosphere] energy flux, in and out, will only be in balance when the Earth has reached thermal equilibrium.   We are not at that point yet ~ even if CO2 (and other Greenhouse gasses) ceased rising immediately, we would still require a few decades for the planet to reach the new [higher] equilibrium point.

    There is no extraction of energy from the atmosphere ~ that question you asked is based on an entirely erroneous concept of the current global warming's mechanism.   If you will, picture the analogy of (say) 4 liters of water inside a sealed steel container ~ but within the water is an electrical immersion heater delivering a steady 20 watts of heat.  Over time, the water will rise to an equilibrium temperature, where the 20 watts in is balancing 20 watts out (the outward flux being by convection & radiation from the steel's outer surface.)  Then coat the steel container with a 1-inch layer of foam rubber.  Then - gradually - you find the water temperature rising to a new higher equilibrium temperature, where the same 20 watts is going in and the same 20 watts is leaving (by convection & radiation from the foam rubber's surface).   The foam rubber "slows down" the energy flux going outwards . . . and you can see how the watery interior needs to be hotter, to get the outermost surface up to the necessary 20 watt total.

    It is only a rough analogy, but it sort of represents a bare planet (without any greenhouse gasses) versus the actual presence of foam-rubber/greenhouse-gasses-in-the-atmosphere type of planet (which we really do have).

    If you wish, add a second 1-inch foam rubber coat on the outside of the first coat.  You can see how the interior water must get even hotter, in order to balance the energy inflow of the same old 20 watts.  [The 20 watts being the analogy to the same old solar radiation input that we've had for the past 50+ years.]

    As you see, the "atmosphere coat" does not generate any energy.  But it can produce a higher or lower temperature for the interior (i.e. the surface of the planet) according to the circumstances of the atmosphere.

  41. The Methane 'Time Bomb': How big a concern?

    I agree jef, methane clathrates are probably the smoking gun from the End Permian Extinction event.

    Methane Hydrate: Killer cause of Earth's greatest mass extinction

     

    We're altering the fundamental balance that determines how warm the Earth's surface is, creating a host of feedbacks making it almost impossible to predict the likely outcome.

    If there is only a 1 in 1 million chance of a massive release of methane into the atmosphere taking climate change completely out of control then that is too much. What if it is much higher than that due to factors we aren't even aware of yet?

    At what point will this be treated as the very real crisis it is.

    Summers here are bad enough with massive wildfire action covering hundreds of thousands of hectares in fires and millions of square kilometers in dense smoke that creates life threatening breathing conditions. Not to mention the heat waves that create the wildfire conditions. And ocean nations dealing with being inundated. And critical habitats in rapid retreat and more.

    At some point complacency becomes delusional.

  42. CO2 effect is saturated

    LTO - Responding to your earlier questions about energy exchange via collisions, and the relative energies of emitting GHGs and the rest of the atmosphere (sorry this is weeks later, just got back to this thread after a while):

    At sea level each molecule in the atmosphere collides with others at about 10^9 times per second. The time for an excited CO2 molecule to emit IR is about 10^-6 seconds. Therefore (comparing relative numbers) each CO2 molecule collides ~1000 times before emitting. Thus the CO2 molecules emit at a rate tied directly to the gas temperature. 

    The tropopause (where the break-even point of CO2 emission lies, ending convection) ranges from about 7 to 20 km, poles to equator. Air pressure at 15km is roughly 100mb, 1/10 sea level, meaning that at that altitude each CO2 molecule collides 100 times with other atmospheric molecules before emitting. So again, CO2 molecules emit at rates tied directly to atmospheric temperature. 

    One side point, since I've seen this a particular error occur repeatedly - emitting CO2 molecules are by no means tied to absorbing CO2 molecules, and neither are the absorption energies directly tied to emission energies on a photon by photon basis. The gases warm due to convection and IR absorption, that temperature gets shared, and the emissions from any particular gas volume are statistical expressions of the GHG emission spectra from GHGs at that temperature. There's no immediate one-to-one connection. 

  43. The Methane 'Time Bomb': How big a concern?

    I find this clip Incredibly disingenuous. We know that the permafrost is warming up all around the world and we also know of no mechanism that will stop or reverse this trend even if we stop co2 over the next 20, 30 years.

    We also know that the arctic oceans are warming and that is the trend for the future regardless of what we do over the next 20 years. Warm water WILL disrupt the clathrates, the Phd is correct that the clathrates don't go into uncontroled collapse by themselves, but warm water will make them ALL melt.

    I understand the desire to not alarm people too much but alarming them too little is worse.

  44. Trenberth on Tracking Earth’s energy: A key to climate variability and change

    I am confused by figure 1 in which there is a net absorption of 0.9W/m2 by the Earth, but the top of the atmosphere is in energy balance.  This implies that global surface warming is extracting this energy from the atmosphere which seems odd if not impossible over the long term.

    Could it be rounding error? and if so, this seems unfortunately misleading (at least to me)

    Cheers

  45. 1934 - hottest year on record

    My apologies. I was really guessing and trying to understand what your beef was. Can perhaps we clarify that?

    I am assuming your beef is with Fig 1. I understand that you are claiming it to be work of fiction because you believe ocean temperature anomaly, particularly in southern hemisphere was unknowable in 1934. (I believe NASA would assert that this is best estimate available from available data and reanalysis methods but they would also acknowledge large error bars). If I have misunderstood you, then please be clearer.

    My point with the 60 station analysis, is that is demonstrates how well methods that perforce assume very large spatial correlation of anomalies work in practise.

    My primary source for how SST derived is Huang et al 2016 but you have chase down the older papers (particular Smith and Reynolds contributions) for errors and validation studies. I do not believe the error estimates for SST in 1900-1941, southern regions (as high as 0.9C) invalidate the figure 1 but maybe I have again misunderstood you.

  46. 1934 - hottest year on record

    ITO,

    Reviewing your posts at 69 and 70 I see no links to any peer reviewed data (and no data analysis at all).  I see only a rambling account of your uninformed opinion.  You provide no statistical evidence (or mention of statistical calculations) to support your wild claims that the temperature record is not supported by enough data.

    We need to review the rules.  This is a scientific web site.  You must produce data to support your wild claims.  I have produced peer reviewed articles to support my claims.  You have provided only your opinion of those articles.  The burden is on you to provide data to support your claims.  If you do not like the articles I cite it is your responsibility to find articles that detail their mistakes or provide detailed calculations that they are incorrect.  Simply stating your unsupported opinion as a random guy on the internet who claimed at the start to not beingvery informed does not carry any weight. 

    Do your homework and read the literature.  If you want to know all the details they are published on the internet.  Find them yourself.  It is  not our responsibility to find all the obscure details that you are interested in.

    You have not demonstrated that you know what a temperature anomaly is.  That knowledge is crucial to our discusion.  As for your unsupported claim that GISS cannot estimate the anomaly over a radius of 1200 km BEST says:"the correlation structure [of the temperature field] is
    substantial out to a distance of ~1000 km, and non-trivial to ~2000 km from each site".  BEST uses a different averaging technique than GISS uses.  When two different groups using different mathmatical techniques agree that the data can be averaged over long distances you need to provide more than "I don't believe it".  Knowing what an anomaly is would help you understand.

    I suggest you restart your discussion and try to learn the basic teminology before you try to reanalyze the data.  You might benifit from reading some of the old posts at Open Mind although you will have to look way back in his blog to find basic discussion of the temperature record.  Realclimate also has good technical discussions of the temperature record in their library.

    You have demonstrated an extraordinary knowledge of denier references to the temperature record.  Please link the web site that you are using to inform yourself so that we can see the original argument.   It probably has already been debunked and we can simply link to that debunk.

  47. 1934 - hottest year on record

    Hi Scadden

    In #86 you assert that I’m trying to assert something that I never have. It’s a weird thing to do. Please just focus on my actual criticisms rather than invent new ones on my behalf.

    In #87 you assert the basis I apparently work on, which is again incorrect.  You either don’t understand the “60 stations” analysis (it’s not actually 60, but that’s not really the point. I address this in #75), or you don’t understand what my criticism is. Read my actual criticisms rather than leaping to conclusions about what you imagine them to be.

    Re Berkeley earth, yes you’re right re proxy data. I meant to make the point that it is land only, and the discussion here is largely about the ocean anomaly ‘data’ shown in the 1934 chart at the top of This page.

  48. 1934 - hottest year on record

    You work on basis that "if you dont have thermometer there, you dont know anything", but as the methodology papers show, that is not the case. If this was so then couldnt reconstruct the temperature from just 60 stations, (massively less than 25% coverage). but as I pointed out earlier, you can.

    I wasnt aware the BEST used proxy data. Can you elaborate? I dont see it in a quick scan of methodology report.

    I found error estimates for other series in a few seconds of search. Which do you want to know?

    The chart is only "a work of fiction" if you discount all the work on estimates of error in global temperature series. The producers of data series publish papers on the methodology which discuss the issues and errors. For you to ignore these and declare the series as "fiction" means the burden of proof does move to you. They have peer-reviewed papers justifying their series. If want to cast doubt, then you need to show us what is wrong with their analysis.

  49. 1934 - hottest year on record

    Hi MA, thanks for the response.

    1. Could you please elaborate on what this "in-filling" is?

    2. With respect, 'lots' isn't a great answer. 25% coverage means no coverage for 75% of the ocean, and yet the 1934 chart shows anomaly readings for roughly 90% of the ocean. Are you saying that the vast majority of the ocean data in the chart is a result of this 'in-filling'. This isn't even getting into issues of reliability of data and calculation of anomalies when a given ship instrument probably never measured precisely the same place at the same time twice.

    3. Yes the Berkeley earth data seem to be one of the few sources that show their errors loud and proud, and as I understand it they use a wide selection of proxy data and acrual measurements to arrive at their estimates. I haven't disputed whether or not 1934 was a cold year globally, but I'm rather saying the chart at the start of this article is massively misleadingp and something of a work of fiction, pretending we know far more about thr global spatial temperature anomalies and with more certainty than we actually do. It raises alarm bells.

  50. 1934 - hottest year on record

    LTO - you seem to be trying to assert that globally,1934 might have hotter than now and doing that by inferring that coverage bias is higher than calculations from comparing spatially separated stations indicate.

    Would you still doubt that it is hotter now than 1934 if you looked at a temperature series that was constructed only from stations operating in 1934? (ie global temperature is being measured on the same basis).

    Infilling. How could you gain confidence that infilling was doing a good job in sparse stations? How about estimating the value of a station only from those around it and comparing with actual value? This is how the error estimates are built. Does it seem a reasonable assumption that the observed variability in SSTs from modern satellite era can be used as basis for estimating the underlying variability in SST in the past as well?

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